Mobile devices such as cellular telephones are regularly used in vehicles. Devices exist which permit the hands-free use of such mobile devices by users operating the vehicles. Hands-free operation of mobile devices is desirable to prevent the dangers associated with operating a mobile device (i.e., holding the mobile device with one hand and/or dialing numbers on the mobile device) while operating a vehicle. Such devices may be built in to the vehicle or carried within the vehicle, such as by being attached to a visor or other structure of the vehicle. In either case, the devices communicate with the mobile device over a short range wireless communications link which enables the communication device to receive audio and/or video input from the user of the mobile device and to output audio and/or video to the user from the party communicating with the mobile device. Communication devices that are not built in to the vehicle are not powered down automatically when the vehicle is shut down. Such devices are powered by a power source, such as a rechargeable battery, that typically continues to provide power to the communication device, even if the vehicle power is shut off. Accordingly, a stand-alone communication device preferably determines when communication with a mobile device is no longer necessary (i.e., when the vehicle is stopped and the user of the mobile device has left the vehicle), disconnects the wireless communication link when communications are no longer necessary, and places the communication device in a low power consumption mode of operation after disconnection.
Known communication devices disconnect the wireless communications link with mobile devices when the mobile device is no longer within range of the communication device. In other words, when the communication device can no longer communicate with the mobile device over the wireless communications link, known communication devices disconnect the wireless communications link and place the communication device into a stand-by or power savings mode to prevent unnecessary power consumption of the communication device when the user fails to manually place the communication device into such a low power mode of operation. Other known communication devices, such as the device disclosed in U.S. Published Application No. 2012/0309388, require that both the communication device and the mobile device include a motion sensor, and disconnect the wireless communication link between the devices when one device is moving while the other device is stationary.
It is not uncommon for the user of the communication device to fail to manually place the communication device into a low power mode of operation and to exit the proximity of the vehicle with the mobile device while remaining within the range of the communication device. For example, many users exit the proximity of the vehicle yet remain within the range of the wireless communications link of the communication device without manually placing the communication device into a low power consumption mode when the user exits the vehicle with the mobile device to enter the user's home. Often, the user parks the vehicle containing the communication device near the user's home, such as in an attached garage, enters the user's home with the mobile device and remains within the range of the wireless communications link of the communication device while in the home. In such circumstances, the user's mobile device remains in communication with the communication device in the vehicle, causing the communication device to unnecessarily consume power and divert calls and other audio and/or video to the communication device when the user is in the home, not in the vehicle where the communication device is located.
Accordingly, it is desirable to provide a communication device and/or a system including a communication device that disconnects the wireless communications link between the communication device and the mobile device when it is determined that the communication device (and therefore the vehicle) is no longer moving, and the mobile device has exited the proximity of the vehicle, even though the mobile device remains within range of the communications link with the communication device.